Dec. 24, 2011: Kim Jong Un, center, North Korean leader Kim Jong Il's youngest known son and successor, with military officials, stand in front of his father's body displayed in a glass coffin, not in photo, at Kumsusan Memorial Palace in Pyongyang, North Korea.
(AP)

North Korea on Sunday aired footage showing the uncle and key patron of anointed heir Kim Jong Un wearing a military uniform with a general's insignia -- a strong sign he'll play a greater role in efforts to secure the young man's rise to power after the death of his father, Kim Jong Il, a week ago.

The footage on state television shows Jang Song Thaek paying respects at Kim Jong Il's body as it lies in state at Kumsusan Memorial Palace. It indicates Jang has been appointed to a new military job. Seoul's Unification Ministry says it's the first time Jang has been shown wearing a military uniform on state TV.

South Korean intelligence has predicted Kim Jong Un's aunt Kim Kyong Hui, a key Workers' Party official, and her husband Jang, who is a vice chairman of the powerful National Defense Commission, will play larger roles supporting the heir.

The North is ramping up its campaign to install Kim Jong Un as the nation's next leader as the mourning for his father continued a week after his death.

North Korea is hailing heir Kim Jong Un as "supreme leader" of the 1.2-million strong military.

Kim Jong Un made a third visit Saturday to the palace where his father's body is lying in state -- this time as "supreme leader of the revolutionary armed forces" and accompanied by North Korea's top military brass, according to the official Korean Central News Agency.

The new title and public show of support from the military leadership sent a strong signal that the nation will maintain Kim Jong Il's "military first" policy for the time being.

Earlier Saturday, the newspaper Rodong Sinmun, mouthpiece of the ruling Workers' Party, urged Kim Jong Un to accept the top military post: "Comrade Kim Jong Un, please assume the supreme commandership, as wished by the people."